Hi,

I'm wondering if I've got a radiator fan issue. I've got two fans on the rad, One big one and one small one. Only the large one seems to be turning on, the small one is always idle, even after long run (with or without A/C on).

 

According to my local auto-electrician there's only a single relay in the engine compartment fuse box and CAN BUS diagnostics seems to only show a single fan output which when triggered, just turns on the big fan.

 

Should the small fan be separately triggered? If so by what conditions? Or is it slaved to the big one so that they both come on together?

 

Can anyone enlighten me as the the normal operation of these fans. (Oh, car has full climatronic A/C fitted if that makes a difference)

Edited 24 June, 201412 yr by SonOfTux

When I have my A/C on I notice that both Fans run, and the more demand on the A/C the faster they run up to around 50% according to VCDS.

 

I have the dual zone climate also. Perhaps a dead motor in the smaller fan? Has it been tested?

Mines the same, Only the bigger one runs with the climate on, Never seen the smaller one running yet??